To further understand mechanisms of the brain, research has focused on fundamental functions of the brain such as learning and memory. Recent discoveries have revealed that a member of the 14-3-3 family of proteins is involved in learning and memory processes. How 14- 3-3 plays a role in these processes is poorly understood. Using learning and memory as a biological assay, 14-3-3 protein function may be revealed. This proposal is designed to characterize proteins which interact with 14-3-3 in learning and memory. The following specific aims are designed to further test the hypothesis that 14-3-3 protein function is essential for learning and memory processes. 1) Identify proteins that interact with 14-3-3. Four Drosophila cDNA clones encoding proteins that interact with 14-3-3 in the yeast two- hybrid system will be sequenced and the interactions of their products with 14-3-3 confirmed by in vitro binding assays and coimmunoprecipitation in yeast and in vivo. 2) Elucidate the expression patterns of 14-3-3 interacting proteins within the brain mRNA and protein expression of 14-3-3 interacting cDNA clones will be determined using Northern analysis, in situ hybridization and immunohistochemistry. 3) Determine the phenotypes of mutants of 14-3-3 interacting proteins. Flies carrying mutations in 14-3-3 interacting protein genes will be tested for deficits in learning and memory using classical olfactory conditioning paradigms.